DPI (Deep Packet Inspection)

In telecom networks, DPI is the inspection of packet payloads beyond headers to classify applications, enforce policy, and detect threats. In a telecom context, DPI is also used to decode encapsulated GTP-U traffic and to identify abusive flows on mobile data networks.

Categories: SignalingThreats and Attacks

DPI in context

Signaling protocols carry the control-plane messages that set up calls, register subscribers and route SMS. SS7, Diameter, GTP-C and SIP are the four dominant families, and interconnect exposure of any of them is treated by GSMA as top-tier telecom risk.

Telecom threats range from opportunistic SMS phishing and SIM swap to nation-state grade location tracking. The common thread is that most attacks exploit the inherited trust model of legacy signaling protocols.

To place DPI in the wider telecom-security picture, review Anomaly Detection, Attack Surface Mapping, DDoS, Denial of Service (DoS), Exposure Mapping and Global Title Abuse — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

More from the TelcoSec Glossary

Browse the full TelcoSec Glossary, the Ultimate Guide to Mobile Network Security, or the P1 Arsenal of telecom-security tools.